1. Field of the Invention
The present invention relates to a receiving apparatus, transmitting apparatus, and reception method, and more particularly to a receiving apparatus, transmitting apparatus, and reception method applied to a radio communication system that uses multiple antennas.
2. Description of the Related Art
To date, intense research and development has been carried out on radio communication systems that use multiple antennas to allow transmission and reception of a greater amount of data in a limited frequency band. Examples of radio communication systems that use multiple antennas are a MIMO (Multiple-Input Multiple-Output) system in which both the transmitting apparatus and receiving apparatus are equipped with a plurality of antennas, and a MISO (Multiple-Input Single-Output) system in which the transmitting apparatus is equipped with a plurality of antennas and the receiving apparatus is equipped with a single antenna.
In a radio communication system that uses this kind of multi-antenna technology, since modulated signals transmitted from a plurality of antennas are multiplexed on a propagation path and received by an antenna at the receiving end, if demodulation processing including signal separation processing cannot be carried out with high precision the receive data error rate characteristics degrade, and as a result, it is not possible to achieve the original aim of increasing the data transmission speed.
Possible ways of improving the precision of separation and demodulation of each modulated signal include increasing the pilot symbols inserted in each modulated signal, but when pilot symbols are increased, propagation efficiency degrades proportionally, with the result that it is not in fact possible to achieve the original aim of increasing the data transmission speed.